1. Field
Embodiments described herein generally relate to gasifiers and methods for the gasification of carbonaceous material. More particularly, such embodiments relate to a gasifier having a transfer line disposed between a cyclone and a standpipe of the gasifier.
2. Description of the Related Art
Gasification is a high-temperature process that converts carbon-containing feedstocks into mostly gaseous mixtures, including carbon monoxide, carbon dioxide, hydrogen, and methane. These gaseous mixtures are typically referred to as synthesis gas or, more succinctly, syngas. Syngas can be used as a source of hydrogen, for the production of other organic chemicals, or to generate steam and/or electricity. Thus, gasification adds value to otherwise low-value feedstocks by converting them to marketable products.
Gasifiers include one or more cyclones adapted to separate and remove solid particulates from the syngas. The particulates can flow through a transfer line to a standpipe where they are recycled back into the system. Conventional transfer lines are in the shape of a block “U” such that the solid particulates flow downward through a first, vertical leg, sideways through a second, horizontal leg, and then upward through a third, vertical leg to reach the standpipe. Oftentimes, an aeration gas is introduced to the transfer line to fluidize the particulates so that they continue to flow therethrough. The aeration gas tends to collect in the top of the horizontal leg causing the particulates in the bottom of the horizontal leg to agglomerate and flow slower than intended or create a blockage.
There is a need, therefore, for an improved gasifier for the gasification of hydrocarbons.